Apparatus for drying continuously moving elongated flexible means



F. KLEINER Nov. 10, 1970 APPARATUS FOR DRYING CONTINUOUSLY MOVING ELONGATED FLEXIBLE MEANS Filed'Oct. 31, 1968 QCQSQQ-..

INVENTOR FQA/UZ (45/0671 RSSACZ/I-I United States Patent 3,538,619 APPARATUS FOR DRYING CONTINUOUSLY MOVING ELONGATED FLEXIBLE MEANS Franz Kleiner, Remscheid, Germany, assignor to Maschinenfabrik Friedrich Haas GmbH & C0., Remscheid-Lennep, Germany Filed Oct. 31, 1968, Ser. No. 772,122 Claims priority, application Germany, Nov. 2, 1967, 1,635,277 Int. Cl. F26b 13/08 U.S. Cl. 34-159 7 Claims ABSTRACT OF THE DISCLOSURE Elongated flexible means, such as spun cables are wound in open loops about staggered rows of perforated driven drums and transported by the same. Streams of hot air are blown by nozzles through the leg portions of the open loops in a first drying circuit, while other streams of hot air blown into the interior of the hollow drums and flow through the perforations of the same past the yoke portions of the open loops so that fast drying is obtained during continuous transport of the elongated flexible means.

BACKGROUND OF THE INVENTION It is known to dry elongated flexible means, such as spun cables by placing the cables in a zigzag formation on a conveyor passing through a drying chamber. Dryers of this type are used in the production of viscous fibers, Cu fibers, and PVY fibers.

It is also known to transport a plurality of cables in adjacent positions over perforated driven drums whose interiors are connected with a suction conduit so that the cables are held on the outer surface of the drums. Drying apparatus of this type require a great number of drums, take up a great deal of space, and are expensive.

SUMMARY OF THE INVENTION It is one object of the invention to provide an apparatus for continuously drying elongated flexible means, such as cables, ropes or bands, which is free of the disadvantages of the dryers according to the prior art, require little space and being of small dimensions.

Another object of the invention is to provide a small drying chamber in which elongated flexible elements are intensively but carefully transported and dried under consideration of the permissible stress.

With these objects in view, and in accordance with the present invention, perforated drums are disposed in upper and lower parallel rows in a drying chamber and driven by a motor to transport elongated flexible means, such as spun cables which are alternately guided over the upper and lower drums in open loops. Between the upper and lower drum, nozzles are located in the open loops and blow hot air against the cables. Intermediate the upper and lower row, open return conduit means are disposed in the open loops. Blower means are located above and below the rows of drums and have inlet means connected with the return conduit means, and outlet means connected by conduits with the nozzles and with the interiors of the hollow drums so that the hot air flows in a first circuit through the nozzles and open loops of the cables, and in a second circuit through the hollow drums, which are open at the ends, to dry loop portions on the drums. It is advantageous to dispose manually controlled valve means in the region where the air stream produced by the blower is divided into the two circuits so that a fine adjustment of the amount of air supplied to the nozzles and to the drums, respectively, is obtained.

In the preferred embodiment of the invention the drive 3,538,619 Patented Nov. 10, 1970 of the drums is adjusted depending on the tension in the transported cables. Since the cables are freely laid in comparatively long open loops, and abut the drums only with the yoke portions of the open loops, a substantial equalization of the tension is obtained. If different tensions occur in successive open loops, they can be equalized by adjusting the relative speed of the transporting drums.

It is advantageous to predry the cables before the same are fed to the drums in the main drying chamber. The preliminary dryer has means for guiding the cables in vertical direction, and is provided with infrared heating means and nozzles which blow hot air. In such an arrangement, a very intensive drying takes place in the preliminary dryer so that the efliciency of the drying apparatus is increased, and the drying chamber, and particularly its floor area can be substantially reduced.

An apparatus according to the invention comprises first and second staggered rows of first and second rotary hollow perforated drums driven for transporting moist elongated flexible means guided alternately over first and second drums so as to form opposite open loops. The loops alternately open between two adjacent first drums and two adjacent second drums, and have leg portions extending between first and second drums and yoke portions located on the drums.

The apparatus further comprises blower nozzles located in the open loops and receiving air heated by heater means to blow the air onto the leg portions of the open loops, and return conduit means disposed between first and second rows of drums in the open loops and communicating with the inlet means of the blower means.

First conduit means connect the outlet means of the blower means with the blower nozzles, and second conduit means connect the outlet means with the interiors of the first and second drums. Consequently, the air flows in two drying circuits from the outlet means of the blower, through the drums, and through the blowers, respectively, and is then drawn from a chamber in which the drums are located to enter the return conduit means and flow from the same to the inlet means of the blower means.

In the preferred embodiment of the invention, the rows of first and second drums are horizontal and located in a drying chamber of casing means, dividing the same into a central chamber portion and into two chamber end portions located outside of the first and second rows of drums. Two blowers have outlet means for blowing air into the end chamber portions where the air passes between heaters and is heated before entering the first and second conduit means. A conduit chamber is located adjacent the drying chamber, and communicates with the inlet means of the blowers, and also with the return conduit means to draw air from the central chamber portion after the air has flown in two circuits through the blower nozzles and through the interior and perforations of the drums.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a schematic side elevation, partially in section, illustrating an apparatus according to the invention; and

FIG. 2 is a cross section taken on line IIII in FIG. 1.

3 DESCRIPTION OF THE PREFERRED EMBODIMENT The casing 1 of the drying apparatus has two drying chambers 1a and 1b, and a preliminary drying chamber 2, separated from each other by vertical walls. As best seen in FIG. 2, a conduit chamber is provided in casing 1 rearward of the drying chamber 1a, and separated from the same by a wall 1d. Another wall 1e separates the conduit chamber 10 from a space If in which drive means are located.

Referring first to the preliminary drying operation carried out in the preliminary drying chamber 2, a flexible elongated means 8, such as a moist cable, rope, or strand of fibrous material, is guided by three guide rollers, 5, 6 and 7 to an opening in the casing to vertically spaced guide rollers 3 and 4 from where the flexible means 8 passes into the drying chamber 1a. A series of flexible means 8 is provided in axially adjacent positions on the guide rollers. Some or all of the guide rollers are driven to move flexible means 8 at a predetermined speed. The vertical portions 8a of the series of flexible means 8 are heated by infrared heaters, and by blower nozzles 9, 10 disposed on opposite sides of portions 8a and blowing hot air against portions 8a. Nozzles 9, 10 penetrate vertical conduits 11, 12 which are advantageously divided into pockets. In the lower part 2a of the preliminary drying chamber 2, a burner 13 is disposed for supplying hot combustion gases into conduits 12 and 11 in which infrared radiators are located which are heated by the combustion gases. Instead of infrared radiator plates heated by combustion gases, electrical or gas heated infrared heaters may be used. The combustion gases and smoke flow in the direction of the arrows through conduits 11 and 12 and flow out of outlet 11a. A rotary blower 14 produces a flow of air which passes through nozzles 9 and 10 and is blovm from opposite sides against portions 8a of the flexible means 8-. The air blown into the preliminary drying chamber by blower 14, is heated by the walls of conduits 11 and 12. If necessary to avoid damage to the fibers of cables forming the flexible means 8, cooling air is blown into the preliminary drying chamber by blower 14 in increased amounts by setting blower 14 to a higher speed and a greater output.

After the moist flexible means 8 have passed through the preliminary drying chamber, they are guided over drums 15 and 16 which are disposed in the drying chamber 1a in an upper row of drums 15 and in a lower row of drums 16. The flexible means passes over a drum 15, then over a drum 16 and again over the next drum 15 so that the opposite loops alternately open between two upper drums 15 and two lower drums 16, and have leg portions 8b extending between upper drums 15 and lower drums 16.

Drums 15 and 16 are hollow and perforated in the peripheral wall thereof, and are supported on shafts 15a and 16a which pass through walls 10! and 1c. The front ends of drums 15 and 16 are free so that flexible means 8 can be easily placed on the same in axially spaced positions when doors and 51 are opened.

Shafts 15a and 16a are driven by pulley and belt drives 18 and 19 from motor 17 so that the flexible means 8 are continuously transported.

The upper and lower rows of drums 15 and 16 divide drying chamber 1a into a central chamber portion 40 and two chamber end portions 41 and 42.

An upper blower 22 and a lower blower 23 are mounted on walls 1d and 1e, and have inlet means communicating with the interior of the conduit chamber 1c, as indicated by arrows. The outlets of blowers 22 and 23 open into the chamber end portions 41 and 42 so that the same serve as outlet chambers. Mesh partitions 24 and 25 divide the outlet chambers 41 and 42 into outlet spaces 41a, 42a, and distributing spaces 41b and 42b. Rows of heater means 26 and 27 are disposed in the distributing 4 chambers 41b and 42b and heat the air flowing between the same as indicated by arrows.

A row of upper blower nozzles 20 and a row of lower blower nozzles 21 are provided and connected with distributing chamber 41b, 42b. Each nozzle 20 is located in an open loop of flexible means 8 between two adjacent upper drums 15, and each nozzle 21 is located in another open loop between adjacent drums 16. Each nozzle 20, 21 has two openings for blowing two air streams against the adjacent leg portions 8b.

It will be seen that air flowing from blowers 22, 23 into the outlet chambers 41, 42 is heated by heaters 26, 27 and flows through the blower nozzles 20, 21 against and through the leg portions 8b of the open loops of the flexible means 8 into the peripheral openings of return conduit means 28 and from there through openings 280 into conduit chamber 1c from which the air is drawn into the inlets of blowers 22, 23 whereby a first drying circuit of the air supplied by the blowers 22 and 23 is completed. As best seen in FIG. 1, a row of return conduits 28 is positioned equidistant from the rows of drums 15 and 16 between the same and located between the leg portions 8b of the open loops formed by flexible means 8. A door 50 permits access into the central chamber portion 40 and to the closed freee nds of return conduit means 28.

Not all the air supplied by blowers 22, 23 and flowing into the distributing chambers 41b, 42b after being heated by heater means 26, 27 flows to the nozzles. Separating wall 1d has openings 29 and 30 in the region of the distributing chambers 41b and 42b which open into conduits formed by walls 33 and 34 which connect openings 29, 30 with the open inner ends of drums 15, and 16, respectively. Manually operable valve means 31 and 32 are located in openings 29 and 30, respectively, which permit the adjustment of the amount of air flowing into the conduits formed by walls 33 and 34. Drums 15 and 16 may have inner and outer cylindrical walls between which the hot air flows until leaving through perforations in the outer cylindrical walls of drums 15 and 16 for drying the yoke portions of the open loops of flexible means 8 located on drums 15 and 16.

Due to this arrangement a second circuit of hot drying air is formed in which the air flows from the blowers through outlet spaces 41, 42, distributing spaces 41b, 42b, openings 29, 30, conduits formed by walls 33, 34, the drums 15 and 16, and through return conduit means 28 into conduit chamber 10 which is connected with the inlets of the blowers 22, 23.

By adjusting valve means 31, 32, the amount of air flowing in the second circuit through the drums is varied, but since the amount of air supplied by blowers 22 and 23 is predetermined, the amount of air flowing in the first circuit is also adjusted so that by adjustment of valves 31, 32 the ratio between the amounts of air flowing in the first and second circuits can be adjusted.

Since the yoke portions of the open loops of the flexible means 8 are in contact with the peripheral walls of drums 15 and 16, heat is transmitted to the same by conduction, while the air stream of the blower nozzles dry the leg portions of the open loops by convection of heat.

Since the yoke portions continuously become leg portions, and the leg portions continuously become yoke portions of the flexible means when the same is transported by the rotating drums 15 and 16, drying is carried out alternately by conduction and convection of heat,.and very eflective.

After drying in the drying chamber 1a, the flexible means 8 may be further dried in a second drying chamber 1b as described for drying chamber 1a, and finally transported out of the apparatus by transporting rollers 45.

It will be understood that each of the elements described above, or two or moretogether, may also find a useful application in other types of drying apparatus differing from the types described above.

While the invention has been illustrated and described as embodied in an apparatus for drying continuously transported elongated flexible cables, ropes, bands or strands by blowing hot air against the same and by guiding the same about heated drums, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any Way from the spirit of the present invention.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

1. Apparatus for drying continuously moving elongated flexible means, comprising, in combination, a drying chamber; first and second staggered rows of first and second rotary hollow perforated drums driven for transporting elongated flexible means guided alternately over first and second drums so as to form opposite loops which are alternately open between two adjacent first drums and two adjacent second drums and have leg portions extending between first and second drums and yoke portions located on said drums, said first and second rows of said first and second drums being located in said drying chamber and dividing the same into a central chamber portion and two chamber end portions located respectively outside of said first and second rows; blower nozzles located between adjacent drums and in said open loops; blower means including first and second blowers having first and second outlets respectively opening into said chamber end portions, and first and second inlets; heater means for heating the air moved by said blower means including first and second rows of heaters located in said chamber end portions of said drying chamber and dividing the same into first and second outlet spaces communicating with said first and second outlets, respectively, and first and second distributing spaces; return conduit means having openings for drawing air and disposed in said central portion of said drying chamber between said first and second rows of said first and second drums in said open loops and connected with said first and second inlets; first conduit means connecting said outlets with said blower nozzles so that hot air is blown by said blower nozzles onto said leg portions of said open loops and then drawn into said return conduit means in a first drying circuit, and second conduit means connecting said outlets with the interiors of said first and second drums, said first and second conduit means communicating with said first and second distributing chambers, the outsides of said first and second drums being connected with said return conduit means so that the hot air flows past said yoke portions of said loops of said flexible elongated means through the perforations of said drums in a second drying circuit.

2. Apparatus as claimed in claim 1 comprising manually operable valve means between said distributing spaces and 6 said second conduit means for varying the ratio between the amounts of air flowing in said first and second conduit means and in said first and second drying circuits.

3. Apparatus as claimed in claim 1 wherein said casing means includes a conduit chamber connected with said first and second inlets of said first and second blowers, and a wall separating said drying chamber from said conduit chamber having openings communicating with said return conduit means.

4. Apparatus as claimed in claim 3 wherein said separating wall has other first and second openings communicating with the interiors of said first and second drums and with said blower nozzles and inlets communicating with said distributing spaces; and wherein said first and second conduit means have walls located in said con duit chamber and communicate with said other first and second openings, respectively, and with said inlets.

5. Apparatus as claimed in claim 4 wherein said nozzles include rows of first and second nozzles respectively located between pairs of adjacent first drums and second drums; and wherein said other first openings include two sets of first openings respectively connected with said first and second nozzles, and two sets of second openings respectively connected with said first and second drums.

6. Apparatus as claimed in claim 5 wherein said casing means have walls forming a preliminary drying chamber adjacent said drying chamber; and comprising means for guiding said elongated flexible means through said preliminary drying chamber and into said drying chamber; blower means, blower nozzles connected with said blower means, infrared heater means, and burner means for heating said heater means and the air so that said elongated flexible means are predried by the heat of said infrared heater means and by the blown air heated by said burner means.

7. Apparatus as claimed in claim 1 comprising drive means for rotating said first and second drums and being adjustable for varying the rotary speed of each drum for adjusting the tension of said open loops.

References Cited UNITED STATES PATENTS 2,199,233 4/1940 Williams 34-159 X 2,585,948 2/1952 Litzler 34-154 X 2,758,356 8/1956 Kawaguchi 34159 X FOREIGN PATENTS 197,097 5/ 1923 Great Britain.

EDWARD J. MICHAEL, Primary Examiner 

